WATERBORNE COATINGS FOR EXTERIORS

Hydroplus. Waterborne coatings for exteriorsWood selectionJoinery design - Bare support processingPrimingWaterborne Topcoat applicationDrying - Packaging materials - Seals -SiliconesCross-linker: cleaning, chemical resistanceWaterborne Topcoat storage - Coating residuesMaterials and equipment - Natural cyclesChoosing the coating cycleWater-based coating cycles for exteriorsHydroplus coatings for exteriorsAdditivesHydroplus Gold

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CONTENTS

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Resistance has always been the first evaluation criterion of exterior-grade wood coatings. With the Hydropluswaterborne coatings, the life of coated wood joinery has considerably increased.

These products are designed for the reduction of water ingress and protection from the sun’s radiation, aswell as for the protection against fungi, and they ensure several advantages in terms of outdoor resistanceand solvent emission reduction.

Longer life on outdoor exposure, twice compared to synthetic products. Waterborne wood coatings keep a highelasticity rate in time, unlike solvent-based products, which due to radical reactions within the film originated byU.V. rays, become so brittle over time that they tend to crack.

Solvent emission abatement: by 90%. Better quality of life for those who apply these products and drasticpollution reduction.

Waterborne coatings are not flammable, can be thinned with tap water, allow fast coating cycles withoutspontaneous combustion and lifting.

HYDROPLUS. WATERBORNE PRODUCTS FOR EXTERIORS

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WATER-BASED WOOD COATINGS ALKYD-BASED WOOD COATINGS

Solvent emission abatement

Not flammable

Equipment can be washed with water

Short drying time

Durability on outdoor exposure

Gloss retention

Non-yellowing film

Resistance to skin formation

Maintains its elasticity on ageing

Lifting resistance (over-coatability)

No spontaneous combustion

Even colour

Better application conditions

Resistance to cold, fungi and bacteria

Initial gloss

Blocking resistance

Chemical resistance

Limited grain raising

Can be applied under more adverse weather

conditions

Advantages arisingrespectively

from the use of waterborne and

alkyd-based products in the manufacture

of joinery for exteriors.

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The Hydroplus clear and pigmented thixotropic Topcoats exhibit good elasticity, no ‘’blocking’’, good verticalbonding, excellent flow and good resistance to settling. In order to ensure a good resistance on outdoor exposure, the clear products of the Hydroplus series areformulated with an optimal dose of U.V. absorbers, with the addition of free radical scavengers. While U.V.absorbers reduce the yellowing and lignin destruction, the U.V. scavengers increase the outdoor life of the film,since they reduce chalking and gloss loss and increase the U.V. absorber efficiency. In the case of pigmentedproducts, the choice of high opacity pigments (with a U.V. filter action), combined with the addition of radicalscavengers, has resulted in the highest quality coatings.

The most important precautions to be observed in the use ofwaterborne coatings are:

During application, for both the product and for the substrate and for the environment, a minimumtemperature of 15°C should be maintained. Films formed below such temperature exhibit lower mechanicaland chemical resistance properties than the standard quality values.

Products must be stored in places with a minimum temperature of 5°C, since they are sensitive to chilling.

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The wood must be healthy and without pith and must exhibit some important features.

There must be no traces of fungal attack; a slight presence of blue stain fungus is allowed.

There must be no traces of insect attack; isolated holes with a maximum diameter of 2 mm on fresh woodare allowed.

There must be no transversal cracking. Longitudinal cracking is only allowed if small and/or fixed withwood.

Sapwood can be present when it has features similar to those of heartwood (e.g. Pine); it is not allowedon woods where sapwood and heartwood have very different features.

Resin pockets can be present if with a maximum width of 5 mm, fixed with wood and not visible aftercoating (for pigmented) or of the same colour (for clear).

Danger of resin outflowPine, Larch, Douglas are rich in natural resin. It is impossible to eliminate or block it by wood drying. Sooner or later,the heat of sun makes it come out. However, only appearance is affected since protection remains unchanged.Always check the wood quality before use.

WOOD SELECTION

The edges must be rounded rather than angled at 45°; the profiles must be inclined at 15° and technical solutionsmust be devised to minimise wood movement, water stagnation and absorption at joints or horizontal components.

JOINERY DESIGN

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All preliminary mechanical processes on bare wood produce an irregular profile on the surface; to obtain a goodcoating result, a regular profile is required, and this can be obtained by sanding with increasingly finer abrasivepaper, up to 150 for soft woods, up to 180 for hard woods.The relative humidity of wood should range between 12% and 14%, according to the wood species.Wood humidity should always be checked before coating, using a moisture meter.

Lacquering with waterborne products according to the woodspecies.

The most suitable woods for outdoor lacquering are Hemlock, Fir and Meranti.Pine, Larch and Douglas cause resin outflow, especially close to the nodes according to their origin, to theperiod of cut of the tree, and its drying. For these reasons, even very highly isolating solvent-based products canensure that resin will never come out, thereby forming yellow halos. This defect is very clear with white and lessclear with other colours.In the case of lacquering of Iroko, Oak and Chestnut, the outflow of tannin compounds (or extracts of varioustypes) causes yellow spots on all or part (for example, only on the upright) of the joinery. Similar problems occurwith Teak, Western Red Cedar and Merbau.

BARE SUPPORT PROCESSING

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This is intended to protect wood moulds. For this reason, the joinery should always be basecoated beforecoating, both in stained and lacquered systems. In stained systems, the Basecoat also serves to absorb U.V.radiation through the transparent oxides that colour it. Natural finishing (carried out with clear Basecoat) are notrecommended since they do not contain iron oxides and therefore do not protect the wood as required,degrading very quickly due to the destruction of lignin. Windows treated with Basecoat only and without Topcoatare not water resistant and the wood may crack. To avoid excessive reduction of the active principlesresponsible for protecting wood, it is not advisable to dilute the Basecoat by more than 10% with water.They can be applied by flow-coating or dipping.

End grain protection

When coating exterior joinery, special care must be taken in the treatment of parts where wood is exposed by itsend grain.In fact, since it is highly absorbing of the coating, with a consequent reduction of the thickness of the applied film,this causes lower protection, especially towards water (humidity, fog, rain, etc.). Water absorption causesdimensional changes in the wood, which in the end grain zone produce tensions on the coating films, which couldcrack and lift from the substrate, with permanent damages to the item.To protect the end grain, apply the water resin sealer with elastic properties XA 481, in order to close all openchannels. This operation must be carried out before the Topcoat is applied on the Basecoat.

BASECOATING

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Hydroplus waterborne coatings can be applied by the normal coating systems (airless, airmix, electrostatic)provided that the equipment construction material is suitable for water contact. Water coatings are alsosuitable to be used in coating systems where the sprayed material is recovered. Special equipment forwater-based coatings is required for electrostatic application.

Equipment not in perfect working order (faulty gaskets, too high pressures) can produce considerable defects inthe film (e.g. air blisters). The use of a pre-atomiser and/or of a pre-heater has given excellent results. The firstone allows obtaining a better coating atomisation, even at lower pressures, reducing air incorporation andincreasing the film transparency. The second one allows better film flow (especially in winter) and a higherTopcoat quality as well as regular results at all times of the year. The pre-heated coating should be between25°C and 35°C. The equipment must be washed immediately after use. If dry coating films are to be removed, useXA 4060, leaving it for 6-12 hours, then rinse with water. Do not use the same pump for applying water- andsolvent-based products.

WATERBORNE TOPCOAT APPLICATION

General indications for the application of clear waterborne products

By cup Nozzle 2,5 mm Pressure 4 bar;

Airmix Nozzle 11-15 Material pressure90-140 bar; air pressure 1-2 bar;

Airless Nozzle 11-15 Material pressure90-140 bar.

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Coating thicknessTo achieve sufficient outdoor resistance, apply a minim wet film of 250 micron on the window and 300 micronon roller shutters. Topcoats of large thickness should not be applied in a single coat since, especially in theaccumulation zones (possible grooves of shaped panels), cracking could be caused by the uneven film drying. Coating thickness should always be checked before using a thickness gauge.

Iron oxidesThe addition of the clear iron oxide-based Pastes XA 4034/** to the Hydroplus clear Topcoats considerablyextends the coating life. In fact, they absorb the ultraviolet component of the solar radiation, improving theprotection of wood.

The drying of waterborne products must take place in rooms with a minimum temperature of 15°C and relativehumidity preferably not exceeding 60%. Outside these limits, the drying is slower and the film could exhibit lower hardness and chemical resistance.Drying should always be performed in places with forced air circulation, preferably dehumidified and slightlywarm (25-35°C). Let the items cool down before stacking, to prevent blocking.

DRYING

Foamed polystyrene, pluri-ball and PVC-based plastic materials are not suitable for packaging items coated withwaterborne products. In practice, on the other hand, foamed polyethylene has given excellent results. A preliminary test should always be performed, given the large variety of materials on the market.

PACKAGING MATERIALS

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Neutral reticulation silicones have shown better adhesion on waterborne coating films. A preliminary test shouldalways be performed, given the large variety of materials on the market.

SILICONES

PVC seals should not be used (also as support base for carriages) since they release plasticizers and thereforesoften and damage the coating film. Thermoplastic seals have shown better results. A preliminary test shouldalways be performed, given the large variety of materials on the market.

SEALS

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To clean waterborne coated items, given their poor resistance to chemicals (e.g. alcohol and ammonia), usesolutions of neutral detergents in lukewarm water. Add small percentages (0.5-1.0%) of Cross-linker XA 4080to the Topcoat while mixing to impart the following enhancements to the coating: chemical resistance (e.g.water, alcohol, ammonia, lime, etc.), hardness and ‘’blocking’’ resistance. The Cross-linker XA 4080, onceadded, lasts 16 hours, after which it must be replaced. In most cases, adding the Cross-linker slightlyincreases viscosity, and therefore the cross-linked coating can be recovered to fresh product after filtering.Note that some Hydroplus Topcoats do not need a Cross-linker. During the first days of application, somewaterborne products produce a surface defect if they come into contact with water, which is similar to asmall blister. The coated material should therefore be protected from water, especially during transportto/from the factory. This phenomenon only occurs when the water drop can stagnate on the item (e.g. ahorizontal surface). Using a Cross-linker in the Topcoat eliminates this problem. Some Topcoats are availablethat do not exhibit this problem. Always check the technical sheet of the products to evaluate the possibility ofadding a Cross-linker.

CROSS-LINKER: CLEANING, CHEMICAL RESISTANCE

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Once the tin has been opened, waterborne coatings can become rotten due to bacteria, moulds and fungicommonly present in the air. This phenomenon is easily detected as it produces bad smells, increase of viscosity,mould on the surface and change of the colour of the product in the tin. Do not recover old products into fresh coating, nor leave open tins for longer periods, especially in summer.Adding the Bactericide XA 4051 extends the product preservability.

WATERBORNE TOPCOAT STORAGE

Coating residues (wash water, booth water, exhaust coating) must be disposed of according to the regulationsin force. Do not throw any residues in the sewers.

COATING RESIDUES

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Given the large variety of materials used for the manufacture of wooden products, when you pass from a solvent-based to a water-based coating system you should always contact the Technical Service to check whether thecomponents used are still suitable or there are more suited ones. To this purpose, check: electrostatic guns,pumps, seals, silicones, adhesives, booth water treatment products, packaging materials, etc.

MATERIALS AND EQUIPMENT

Exposed or partly exposed items should not be colourless or in neutral colour, that is, coated with clear Primers,since they do not contain iron oxides and therefore do not offer sufficient protection on outdoor exposure (woodcolour variations, lignin abatement, etc.).

NATURAL CYCLES

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CHOOSING THE COATING CYCLE

Two factors must be considered in theevaluation of the minimum coatingthickness to be applied and of the mostsuitable cycle to apply to a wood item forexteriors: the hazard class and the woodspecies.As regards the hazard class, in general,two-coat cycles are sufficient for windowsprotected by rolling shutters; whilethree-coat cycles are required forunprotected windows.As regards the wood species, broad-leavedwoods (Oak, Chestnut, Meranti), with deeppores, require larger final dry thicknessthan conifer woods (Fir, Pine, Larch,Douglas).

COATINGCYCLES

WOOD SPECIES

CONIFERS BROAD-LEAVED WOODS

Fir, Pine, Hemlock

Douglas, Larch1, Pitch PineMeranti Oak, Iroko3, Chestnut

Fir2 , Hemlock Meranti

Windows Shutters Windows Shutters Windows Shutters

Windows Shutters Windows Shutters Windows Shutters

1: Russian-origin larch excluded, as it contains very high quantities of resin.2: can produce node yellowing due to the outflow of natural resin.3: mineral salt exudations with coating film darkening can occur.

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Excellent Good Sufficient

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WATER-BASED COATING CYCLES FOR EXTERIORS

Two-coat clear cycleCYCLE 1

AM 546 Drying: 4 hoursAutomatic or manual denibbing the day after

AZ 20**Stacking after 24 hours

Three-coat clear cycleCYCLE 2

AM 546 Drying: 4 hours

AM 480 Drying: 6 hoursAutomatic polishing or manual smoothing the day after




AM 475 Drying: 6 hoursManual smoothing the day after




AZ 20** Drying: 90-120 minutes


or


AZ 20** Drying: 16 hoursManual denibbing the day after


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Two-coat clear cycleCYCLE 5









AZ 20** Drying: 90-120 minutos


or


AZ 20** Drying: 16 hoursManual smoothing the day after




AM 475/85 Drying: 6 hoursManual denibbing the day after


Three-coat white lacquered cycleCYCLE 9

AM 541/13 Drying: 4 hours

AM 541/13 Drying: 8 hoursAutomatic or manual denibbing the day after

AZ 2030/13Stacking after 24 hours

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AM 475/13 Drying: 6 hoursManual denibbing the day after



AM 541/13 Drying: 4 hoursAutomatic or manual denibbing the day after

AZ 2030/13 Drying: 90-120 minutos


or


AZ 2030/13 Drying: 16 hoursManual denibbing the day after


Three-coat sundry coloured lacquered cycleCYCLE 12


AZ 2030 Drying: 90-120 minutos

AZ 2030Stacking after 24 hours

or


AZ 20** Drying: 16 hoursManual denibbing the day after

AZ 2030Stacking after 24 hours

AM 546It is a specific clear Primer for conifers and Meranti. Itsinnovative formulation allows obtaining a very highevenness and reduced greying for any very porouswood, such as Hemlock and Fir. The excellent flow and quick drying cause reduced fibreand grain raising. The use of selected clear iron oxides ensures an effective barrier against U.V. rays, which cause lignindegradation. In addition, the presence of a powerful fungicide prevents the attack of fungi and moulds. TheBasecoat is available in several colours to meet all ofthe client requirements:00 Clear, 51 Chestnut, 66 Hedge Green, 84 AmericanWalnut, 85 Larch, 88 Walnut Brown, 89 Teak, 90Mahogany, 92 Walnut, 95 Dark Walnut.

AM 549It is a high-performance clear Basecoat for broad-leavedwoods rich in extracts, such as Iroko, Oak and Chestnut.Its tested formulation allows priming woods without theneed of sealers, without problems of flow and with a little fibre raising. The combined action of clear ironoxides and of the fungicide ensure a high protectionover time. The Basecoat is available in a wide range ofcolours:00 Clear, 51 Chestnut, 66 Hedge Green, 80 Oak, 82 Pine,84 American Walnut, 85 Larch, 90 Mahogany, 92 Walnut.

AM 512It is a specific coloured Primer for attic beams, especially suitable for conifers. Its formulation allowsautomatic denibbing. The presence of iron oxide and ofthe fungicide help in preserving its performance and aesthetic features over time. It is available in twocolours: 51 Chestnut and 70 Honey.

AM 541It is a pigmented sealing Primer combining a very highcovering with excellent flow. Especially suitable for yellowing and reddening caused by the extracts of somewoods. It protects the item from moulds and fungi,thanks to the fungicide contained in its formulation.It is available in the following colours: N0 Neutral(can be pigmented with the Pastes of the XA 4099series), 01 Ivory, 13 White, 66 Hedge Green.

HYDROPLUS COATINGS FOR EXTERIORS

PRIMERS

AM 480This Intermediate coat exhibits high covering andtransparency, excellent flow and excellent ability ofwetting the wood pore and penetration in all criticalzones of the item. It exhibits good manual and automaticsandability. It contains preservatives to increase theitem life in time.

AM 483It is a medium covering clear Intermediate especiallysuitable for automatic denibbing. It exhibits a goodflow that allows it to also protect parts that are noteasily accessed by the following coat.

INTERMEDIATE COATS

AM 473This is a clear or lacquered thixotropic Basecoat withgood sandability, high solid content and good covering.It is suitable for porous woods, such as Meranti andOkoumè, for its good pore wetability. Available in boththe Clear version (00) and in White (13).

AM 475It is a clear or lacquered thixotropic Basecoat especiallysuitable for automatic sanding. Easy to apply andenriched with fungicide, it is the top of the range.Available both in Clear (00), and Larch (85) with cleariron oxides to give a warmer effect and higherprotection. In the pigmented version, it is available inWhite (13) and Green (33), besides the Neutral, whichcan be pigmented up to 3% with the Pastes of theXA 4099 series.

AM 488/85This is a clear sealing Basecoat that can effectively

block the release of the Iroko gum. It exhibits goodsandability and covering.

AM 462This is a pigmented single-component thixotropicBasecoat with excellent isolating power towardsextracts such as tannin, gums, etc. and resin of somewoods. Easy to apply and with good wetability, it isideal for any type of application. It is available in N0version, which can be pigmented with the Pastes ofthe XA 4099 series, and in White (13) and Green (33).

AM 562This is a pigmented or clear two-componentthixotropic Basecoat to be catalysed with 10% AH1545. It is excellent for blocking extracts and resineven in difficult to coat woods. Unlike the otherBasecoats, it exhibits high resistance to chemicalsubstances and high film hardness. It exhibits a goodsandability.

BASECOATS

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AZ 20**This is a clear or pigmented thixotropic Topcoat withproven durability and reliability. It exhibits good elasticityand is easy to apply, and therefore it is suitable for anytype of application. No ‘’blocking’’ and lifting, andgood flow are the strengths of this product. Thepresence of selected resins and U.V. absorbers allowforming a protective film capable of blocking thenegative action of sun and water. It is available in Larch (85) at 20, 30, 45, 60 gloss; Clear(00) and Dark Walnut (95) at 30 gloss; in Teak (89) at 20and 30 gloss. In the lacquered version at 30 gloss inWhite (13), Lawn Green (33), Ice White (41), HedgeGreen (66).

AZ 21**This is a clear or lacquered thixotropic Topcoatwith excellent water and humidity resistance, andhigh item wetability. It exhibits good flow andtransparency. The presence of U.V. absorbers allows protectionfrom the sun. It is available in Larch (85) at 45, 30, 45,60 gloss; Clear (00) and Teak (89) at 30 gloss. In the lacquered version at 30 gloss in White (13), Ice White(41), Hedge Green (66) and Neutral (N0).

AZ 22**This is a clear or lacquered thixotropic Topcoat withthe highest solid content in the range, that allows giving an excellent covering to the item. It exhibits good water resistance and flow. Availablein 35 and 60 gloss versions, the clear Topcoat is available in Larch (85) at 35, 45 and 60 gloss and Teak(89) at 35 gloss; the lacquered topcoat is available inWhite (13), Lawn Green (33), Brown (65), Ice White(41), Hedge Green (66).

XA 99**This is a thixotropic Topcoat for colour matching systems available in Neutral (NN) and White (BB) andin 15, 30, 45, 60 gloss. The Topcoat must be pigmentedwith the special Pastes of the XA 4099 series.

HYDROPLUS TOPCOATS

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To keep the chemical and physical characteristics of Hydroplus waterborne products unchanged over time, thefollowing range of Additives is available:

ADDITIVES

Clear and lacquered Topcoats


Primers and Intermediates

Clear and lacquered Topcoats and Basecoats, Primers, Intermediates

Primers of the AM 546 series

Primers of the AM 549, AM 512 series





To clean the frame surface



To apply to head woods before the Topcoat.

XA 4009

XA 4017

XA 4024

XA 4026

XA 4034/B2, B7, 72

XA 4034/08, 52, 53, 65, 72

XA 4044/66, 90, 92, 93

XA 4051

XA 4057

XA 4059

XA 4060

XA 4066

XA 4080

XA 481

Matt paste

Stabiliser

Anti-foam for flow-coating

Retardant

Clear iron oxides

Clear iron oxides

Iron oxides

Preservative

Anti-cissing

Anti-foam

Detergent

Thickening agent

Cross-linker

Sealer

Code Description Application

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HYDROPLUS GOLD

CLEAR GOLD CYCLE

AM 303/89, 90, 93 Clear Primer for conifer

AM 306/89, 90, 93 Clear Primer for broad-leaved woods

AM 603/91 Clear Intermediate

AZ 9030/86 Clear thixotropic Topcoat at gloss

PIGMENTED GOLD CYCLE

AM 309/13, 66 Pigmented Primer

AM 609/13, 33 Pigmented thixotropic Basecoat

AZ 9030/13 White pigmented thixotropic Topcoat at 30 gloss

AZ 9060/13 White pigmented thixotropic Topcoat at 60 gloss

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ARCH COATINGS UK Ltd - A1 Business Park - KnottingleyWest Yorkshire - WF11 0BU - Englandph. +44 (0) 1977 673363 - fax +44 (0) 1977 [email protected] - www.archcoatings.co.ukCustomer service: ph. +39 051 770770fax +39 051 770521 - [email protected]

ARCH COATINGS USA - Highway 933, P.O. BOX 547Brandeburg, KY 40108ph. +1 270 4226860 - fax +1 270 [email protected] - www.sayerlack.itCustomer service: ph. +39 051 770770fax +39 051 770521 - [email protected]

ARCH CHEMICALS COATINGS SINGAPORE Pte Ltd1 Kim Seng Promenade - #13-09 Great World City West TowerSingapore 237994 - ph. +65 67351268 - fax +65 [email protected] - www.sayerlack.itCustomer service: ph. +39 051 770770fax +39 051 770521 - [email protected]

ARCH COATINGS EXPORT DEPT.Via del Fiffo, 12 - 40065 Pianoro (BO) Italiaph. +39 051 770511 - fax +39 051 770527 [email protected] - www.sayerlack.itCustomer service: ph. +39 051 770770fax +39 051 770521 - [email protected]

WATERBORNE COATINGS FOR EXTERIORS

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